Nested system operation

ABSTRACT

Methods, systems, and devices are described for resource scheduling for different services in a wireless communications system. A base station or a user equipment (UE) operating within a wireless communication system may, for example, communicate using two or more different configurations of resource (e.g., symbol) duration, while maintaining a common tone spacing, bandwidth, transmission time interval (TTI) designation, or the like. For instance, an orthogonal frequency division multiplexing (OFDM) symbol may be subdivided or segmented, and each segment, which may include a cyclic prefix, may be utilized as a resource unit.

CROSS REFERENCES

The present Application for Patent is a Continuation of U.S. patentapplication Ser. No. 14/957,417 by Luo et al., entitled, “NESTED SYSTEMOPERATION” filed Dec. 2, 2015, which claims priority to U.S. ProvisionalPatent Application No. 62/104,629 by Luo et al., entitled “NESTED SYSTEMOPERATION,” filed Jan. 16, 2015, and U.S. Provisional Patent ApplicationNo. 62/089,792 by Luo et al., entitled “NESTED SYSTEM OPERATION,” filedDec. 9, 2014, assigned to the assignee hereof, and expresslyincorporated by reference herein.

BACKGROUND Field of the Disclosure

The present disclosure, relates to wireless communication systems, andmore particularly to techniques for resource scheduling for differentservices in wireless communications systems.

Description of Related Art

Wireless communication systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be multiple-accesssystems capable of supporting communication with multiple users bysharing the available system resources (e.g., time, frequency, andpower). Examples of such multiple-access systems include code-divisionmultiple access (CDMA) systems, time-division multiple access (TDMA)systems, frequency-division multiple access (FDMA) systems, andorthogonal frequency-division multiple access (OFDMA) systems.

By way of example, a wireless multiple-access communication system mayinclude a number of base stations, each simultaneously supportingcommunication for multiple communication devices, otherwise known asuser equipment (UEs). A base station may communicate with UEs ondownlink channels (e.g., for transmissions from a base station to a UE)and uplink channels (e.g., for transmissions from a UE to a basestation).

As technology advances, some more advanced mobile devices within awireless communications network may have capabilities in whichcommunications are transmitted according to different timingcharacteristics or transmissions have different control informationrelative to legacy mobile devices (e.g., devices operating according toprior industry standards) that operate within the network. Resourceswithin the network may be used to provide services to the advancedmobile devices as well as the legacy mobile devices, or may be used toprovide different types of services to advanced mobile devices. Incertain situations, it may be desirable to provide flexibility inallocation of resources of a wireless communications network based ondifferent mobile devices in order to support the advanced mobile devicesas well as provide backward compatibility for legacy mobile devices.

SUMMARY

Systems, methods, and devices for resource scheduling and utilization ina wireless communications system are described. A base station or a userequipment (UE) operating within a wireless communication system may, forexample, communicate using two or more different configurations ofresource (e.g., symbol) duration, while maintaining a common tonespacing, bandwidth, transmission time interval (TTI) designation, or thelike. For instance, an orthogonal frequency division multiplexing (OFDM)symbol may be subdivided or segmented, and each segment, which mayinclude a cyclic prefix, may be utilized as a resource unit.

A method of communication at a wireless device is described. The methodmay include configuring a first resource segment having a first durationthat is less than a symbol period, configuring a second resource segmenthaving a second duration that is less than the symbol period, where atotal duration of the first and second durations is less than or equalto the symbol period, and communicating utilizing the configured firstand second resource segments.

An apparatus for communication at a wireless device is described. Theapparatus may include means for configuring a first resource segmenthaving a first duration that is less than a symbol period, means forconfiguring a second resource segment having a second duration that isless than the symbol period, where a total duration of the first andsecond durations is less than or equal to the symbol period, and meansfor communicating utilizing the configured first and second resourcesegments.

A further apparatus for communication at a wireless device is described.The apparatus may include a processor, memory in electroniccommunication with the processor, and instructions stored in the memory.The instructions may be executable by the processor to cause theapparatus to configure a first resource segment having a first durationthat is less than a symbol period, configure a second resource segmenthaving a second duration that is less than the symbol period, where atotal duration of the first and second durations is less than or equalto the symbol period, and communicate utilizing the configured first andsecond resource segments.

A non-transitory computer-readable medium storing code for communicationat a wireless device is described. The code may include instructionsexecutable to configure a first resource segment having a first durationthat is less than a symbol period, configure a second resource segmenthaving a second duration that is less than the symbol period, where atotal duration of the first and second durations is less than or equalto the symbol period, and communicate utilizing the configured first andsecond resource segments.

Some examples of the method, apparatuses, or non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for configuring a symbol having thesymbol period, where communicating with the wireless device includescommunicating utilizing the configured symbol the configured first andsecond resource segments. Additionally or alternatively, in someexamples, communicating includes communicating utilizing the configuredsymbol and the configured first and second resource segments in a commonsubframe.

In some examples of the method, apparatuses, or non-transitorycomputer-readable medium described above, the first resource segmentincludes a first cyclic prefix (CP), and the second resource segmentincludes a second CP. In some examples, communicating includestransmitting a control or data signal in the first resource segment, thesecond resource segment, and a symbol having the symbol period. Thecontrol or data signal spans the first and second durations and thesymbol period.

Some examples of the method, apparatuses, or non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for configuring a third resourcesegment having a third duration that is less than the symbol period,where a total duration of the first, second, and third durations isgreater than the symbol period, and communicating utilizing theconfigured first, second, and third resource segments. Additionally oralternatively, in some examples, communicating includes transmitting acontrol or data signal in the first resource segment, the secondresource segment, and the third resource segment, where the control ordata signal spans the first, second, and third durations.

In some examples of the method, apparatuses, or non-transitorycomputer-readable medium described above, the first resource segment,the second resource segment, or a combination thereof includes ademodulation reference signal (DMRS). Additionally or alternatively, insome examples, a symbol includes a portion of the DMRS, the symbolhaving the symbol period, where the DMRS spans the first and seconddurations and the symbol period.

In some examples of the method, apparatuses, or non-transitorycomputer-readable medium described above, the first resource segment,the second resource segment, or combination thereof includes acell-specific reference signals (CRS). Additionally or alternatively, insome examples, a symbol includes a portion of the CRS, the symbol havingthe symbol period, where the CRS spans the first and second durationsand the symbol period.

The first and second resource segments may include frequency resourcesof a first component carrier, and some examples of the method,apparatuses, or non-transitory computer-readable medium described abovemay further include processes, features, means, or instructions forscheduling the frequency resources of the first component carrierutilizing frequency resources of a second component carrier.Additionally or alternatively, some examples, processes, features,means, or instructions for receiving feedback related to the first orsecond resource segments on the frequency resources of the secondcomponent carrier.

In some examples of the method, apparatuses, or non-transitorycomputer-readable medium described above, the first resource segment,the second resource segment, or combination thereof includes a channelstate information (CSI) reference signal. Additionally or alternatively,in some examples, a symbol includes a portion of the CSI referencesignal, the symbol having the symbol duration, and where the CSIreference signal spans the first and second durations and the symbolperiod.

A further method of communication at a wireless device is alsodescribed. The method may include identifying a first resource segmenthaving a first duration that is less than a symbol period, identifying asecond resource segment having a second duration that is less than thesymbol period, where a total duration of the first and second durationsis less than or equal to the symbol period, and communicating with anode utilizing the first and second resource segments.

A further apparatus for communication at a wireless device is alsodescribed. The apparatus may include means for identifying a firstresource segment having a first duration that is less than a symbolperiod, means for identifying a second resource segment having a secondduration that is less than the symbol period, where a total duration ofthe first and second durations is less than or equal to the symbolperiod, and means for communicating with a node utilizing the first andsecond resource segments.

A further apparatus for communication at a wireless device is alsodescribed. The apparatus may include a processor, memory in electroniccommunication with the processor, and instructions stored in the memory.The instructions may be executable by the processor to cause theapparatus to identify a first resource segment having a first durationthat is less than a symbol period, identify a second resource segmenthaving a second duration that is less than the symbol period, where atotal duration of the first and second durations is less than or equalto the symbol period, and communicate with a node utilizing the firstand second resource segments.

A further non-transitory computer-readable medium storing code forcommunication at a wireless device is also described. The code mayinclude instructions executable to identify a first resource segmenthaving a first duration that is less than a symbol period, identify asecond resource segment having a second duration that is less than thesymbol period, where a total duration of the first and second durationsis less than or equal to the symbol period, and communicate with a nodeutilizing the first and second resource segments.

Some examples of the method, apparatuses, or non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for identifying a symbol having thesymbol period, where communicating includes communicating utilizing thesymbol and the first and second resource segments. Additionally oralternatively, in some examples, communicating with the node includescommunicating utilizing the symbol and the first and second resourcesegments in a common subframe.

In some examples of the method, apparatuses, or non-transitorycomputer-readable medium described above, the first resource segmentincludes a first CP, and the second resource segment includes a secondCP. Additionally or alternatively, in some examples, communicating withthe node includes receiving a control or data signal in the firstresource segment, the second resource segment, and a symbol having thesymbol period, where the control or data signal spans the first andsecond durations and the symbol period.

Some examples of the method, apparatuses, or non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for identifying a third resourcesegment having a third duration that is less than the symbol period,where a total duration of the first, second, and third durations isgreater than the symbol period, and communicating utilizing the first,second, and third resource segments. Additionally or alternatively, insome examples, communicating with the node includes receiving a controlor data signal in the first resource segment, the second resourcesegment, and the third resource segments, where the control or datasignal spans the first, second, and third durations.

In some examples of the method, apparatuses, or non-transitorycomputer-readable medium described above, the first resource segment,the second resource segment, or combination thereof includes a DMRS.Additionally or alternatively, in some examples a symbol includes aportion of the DMRS, the symbol having the symbol period, and the DMRSspans the first and second durations and the symbol period.

In some examples of the method, apparatuses, or non-transitorycomputer-readable medium described above, the first resource segment,the second resource segment, or combination thereof includes a CRS.Additionally or alternatively, in some examples, a symbol includes aportion of the CRS, the symbol having the symbol period, and the CRSspans the first and second durations and the symbol period.

In some examples of the method, apparatuses, or non-transitorycomputer-readable medium described above, the first resource segment,the second resource segment, or combination thereof includes a CSIreference signal. Additionally or alternatively, in some examples, asymbol includes a portion of the CSI reference signal, the symbol havingthe symbol period, and the CSI reference signal spans the first andsecond durations and the symbol period.

The first and second resource segments may include frequency resourcesof a first component carrier, and some examples of the method,apparatuses, or non-transitory computer-readable medium described abovemay further include processes, features, means, or instructions forreceiving grants for the frequency resources of the first componentcarrier utilizing frequency resources of a second component carrier.Additionally or alternatively, some examples, processes, features,means, or instructions for transmitting feedback related to the first orsecond resource segments on the frequency resources of the secondcomponent carrier.

The foregoing has outlined rather broadly the features and technicaladvantages of examples according to the disclosure in order that thedetailed description that follows may be better understood. Additionalfeatures and advantages will be described hereinafter. The conceptionand specific examples disclosed may be readily utilized as a basis formodifying or designing other structures for carrying out the samepurposes of the present disclosure. Such equivalent constructions do notdepart from the scope of the appended claims. Characteristics of theconcepts disclosed herein, both their organization and method ofoperation, together with associated advantages will be better understoodfrom the following description when considered in connection with theaccompanying figures. Each of the figures is provided for the purpose ofillustration and description only, and not as a definition of the limitsof the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

A further understanding of the nature and advantages of the presentinvention may be realized by reference to the following drawings. In theappended figures, similar components or features may have the samereference label. Further, various components of the same type may bedistinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If only the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label.

FIG. 1 illustrates an example of a wireless communications system thatsupports nested system operation in accordance with various aspects ofthe present disclosure;

FIG. 2 illustrates an example of a frame structure that may be used in awireless communication system to support nested system operation inaccordance with various aspects of the present disclosure;

FIG. 3A illustrates an example of a block diagram conceptuallyillustrating an example of a radio frame and different subframes thatmay be transmitted or received in accordance with various aspects of thepresent disclosure;

FIG. 3B illustrates an example of a block diagram conceptuallyillustrating an example of cross carrier scheduling in accordance withvarious aspects of the present disclosure;

FIGS. 4A, 4B, and 4C illustrate examples of a block diagramsconceptually illustrating examples of radio subframes that may betransmitted or received in accordance with various aspects of thepresent disclosure;

FIG. 5 shows a block diagram of a device that supports nested systemoperation in accordance with various aspects of the present disclosure;

FIG. 6 shows a block diagram of a device that supports nested systemoperation in accordance with various aspects of the present disclosure;

FIG. 7 shows a block diagram of a symbol adaptation module that supportsnested system operation in accordance with various aspects of thepresent disclosure;

FIG. 8 illustrates a block diagram of a system including a mobile devicethat supports nested system operation in accordance with various aspectsof the present disclosure;

FIG. 9 illustrates a block diagram of a system including a base stationthat supports nested system operation in accordance with various aspectsof the present disclosure;

FIG. 10 shows a flowchart illustrating a method for nested systemoperation in accordance with various aspects of the present disclosure;

FIG. 11 shows a flowchart illustrating a method for nested systemoperation in accordance with various aspects of the present disclosure;

FIG. 12 shows a flowchart illustrating a method for nested systemoperation in accordance with various aspects of the present disclosure;

FIG. 13 shows a flowchart illustrating a method for nested systemoperation in accordance with various aspects of the present disclosure;

FIG. 14 shows a flowchart illustrating a method for nested systemoperation in accordance with various aspects of the present disclosure;and

FIG. 15 shows a flowchart illustrating a method for nested systemoperation in accordance with various aspects of the present disclosure.

DETAILED DESCRIPTION

Techniques are described for resource scheduling for different types ofcommunications, and for supporting devices operating according todifferent versions of a communication standard. This may generally bedescribed as nested system operation. In some examples, a base stationand one or several user equipments (UEs) may be configured to operatewithin a wireless communication system using different configurations ofresource (e.g., symbol) duration. Resources within a system may beconfigured to support communication—e.g., low latency requirements forcertain devices—while maintaining compatibility with legacydevices—e.g., devices operating according to a prior version of acommunications standard. In order to offer benefits to new devices, suchas supporting low latency operations or an enhanced component carrier,resources may be configured to complement systems having well-definedtone spacing, symbol duration, bandwidth, transmission time interval(TTI), and the like. Physical resources configured according to onenumerology may thus be nested within a system generally configured tooperate according to a different numerology.

The following description provides examples, and is not limiting of thescope, applicability, or examples set forth in the claims. Changes maybe made in the function and arrangement of elements discussed withoutdeparting from the scope of the disclosure. Various examples may omit,substitute, or add various procedures or components as appropriate. Forinstance, the methods described may be performed in an order differentfrom that described, and various steps may be added, omitted, orcombined. Also, features described with respect to some examples may becombined in other examples.

Referring first to FIG. 1, a diagram illustrates an example of awireless communications system 100, in accordance with an aspect of thepresent disclosure. The wireless communications system 100 includes aplurality of base stations (e.g., eNBs, or WLAN access points) 105,which may also be referred to as access points, a number of userequipment (UEs) 115, and a core network 130. Some of the base stations105 may communicate with the UEs 115 under the control of a base stationcontroller (not shown), which may be part of the core network 130 or thecertain base stations 105 (e.g., eNBs or other access points) in variousexamples. Base stations 105 may communicate control information and/oruser data with the core network 130 through backhaul links 132. Inexamples, the base stations 105 may communicate, either directly orindirectly, with each other over backhaul links 134, which may be wiredor wireless communication links. The wireless communications system 100may support operation on multiple carriers (waveform signals ofdifferent frequencies). Multi-carrier transmitters can transmitmodulated signals simultaneously on the multiple carriers. For example,each communication link 125 may be a multi-carrier signal modulatedaccording to the various radio technologies described above. Eachmodulated signal may be sent on a different carrier and may carrycontrol information (e.g., reference signals, control channels, etc.),overhead information, data, etc.

The base stations 105 may wirelessly communicate with the UEs 115 viaone or more access point antennas. Each of the base stations 105 sitesmay provide communication coverage for a respective coverage area 110.In some examples, base stations 105 may be referred to as a basetransceiver station, a radio base station, a radio transceiver, a basicservice set (BSS), an extended service set (ESS), a NodeB, eNodeB, HomeNodeB, a Home eNodeB, or some other suitable terminology. The coveragearea 110 for a base station may be divided into sectors making up only aportion of the coverage area (not shown). The wireless communicationssystem 100 may include base stations 105 of different types (e.g.,macro, micro, and/or pico base stations). The base stations 105 may alsoutilize different radio technologies, such as cellular and/or WLAN radioaccess technologies, and may thus be referred to as access points. Thebase stations 105 may be associated with the same or different accessnetworks or operator deployments. The coverage areas of different basestations 105, including the coverage areas of the same or differenttypes of base stations 105, utilizing the same or different radiotechnologies, and/or belonging to the same or different access networks,may overlap.

In LTE/LTE-A network communication systems, the terms evolved Node B(eNodeB or eNB) may be generally used to describe the base stations 105.The wireless communications system 100 may be a Heterogeneous LTE/LTE-Anetwork in which different types of access points provide coverage forvarious geographical regions. For example, each base station 105 mayprovide communication coverage for a macro cell, a pico cell, a femtocell, and/or other types of cell. Small cells such as pico cells, femtocells, and/or other types of cells may include low power nodes or LPNs.A macro cell generally covers a relatively large geographic area (e.g.,several kilometers in radius) and may allow unrestricted access by UEs115 with service subscriptions with the network provider. A small cellwould generally cover a relatively smaller geographic area and may allowunrestricted access by UEs 115 with service subscriptions with thenetwork provider, for example, and in addition to unrestricted access,may also provide restricted access by UEs 115 having an association withthe small cell (e.g., UEs in a closed subscriber group (CSG), UEs forusers in the home, and the like). An eNB for a macro cell may bereferred to as a macro eNB. An eNB for a small cell may be referred toas a small cell eNB. An eNB may support one or multiple (e.g., two,three, four, and the like) cells.

The core network 130 may communicate with the base stations 105 (e.g.,eNBs or other access points) via a backhaul link 132 (e.g., S1interface, etc.). The base stations 105 may also communicate with oneanother, e.g., directly or indirectly via backhaul links 134 (e.g., X2interface, etc.) and/or via backhaul links 132 (e.g., through corenetwork 130). The wireless communications system 100 may supportsynchronous or asynchronous operation. For synchronous operation, thebase stations 105 may have similar frame timing, and transmissions fromdifferent base stations 105 may be approximately aligned in time. Forasynchronous operation, the base stations 105 may have different frametiming, and transmissions from different base stations 105 may not bealigned in time. The techniques described herein may be used for eithersynchronous or asynchronous operations.

The UEs 115 are dispersed throughout the wireless communications system100, and each UE 115 may be stationary or mobile. A UE 115 may also bereferred to by those skilled in the art as a mobile station, asubscriber station, a mobile unit, a subscriber unit, a wireless unit, aremote unit, a mobile device, a wireless device, a wirelesscommunications device, a remote device, a mobile subscriber station, anaccess terminal, a mobile terminal, a wireless terminal, a remoteterminal, a handset, a user agent, a mobile client, a client, or someother suitable terminology. A UE 115 may be a cellular phone, a personaldigital assistant (PDA), a wireless modem, a wireless communicationdevice, a handheld device, a tablet computer, a laptop computer, acordless phone, a wearable item such as a watch or glasses, a wirelesslocal loop (WLL) station, or the like. A UE 115 may be able tocommunicate with macro eNodeBs, small cell eNodeBs, relays, and thelike. A UE 115 may also be able to communicate over different accessnetworks, such as cellular or other WWAN access networks, or WLAN accessnetworks. Various UEs 115 within the system 100 may operate according todifferent wireless standards, or according to different versions (e.g.,“releases”) of a particular wireless standard. For example, certain UEs115 may operate according to a version particular version of the LTEstandard (e.g., LTE Release 11 or earlier). These devices may bereferred to as legacy UEs because they utilize a legacy, or priorrelease of an existing standard. Likewise, other UEs 115 may operateaccording to a different version of the LTE standard (e.g., post-Release11), or such devices may employ features beyond those specified in theLTE standard. Such UEs 115 may be referred to as non-legacy UEs,advanced UEs, enhanced UEs, low latency UEs, hybrid UEs, or the like.

The communication links 125 shown in wireless communications system 100may include uplink (UL) transmissions from a UE 115 to a base station105, or downlink (DL) transmissions, from a base station 105 to a UE115. The downlink transmissions may also be called forward linktransmissions while the uplink transmissions may also be called reverselink transmissions. Each communication link 125 may include one or morecarriers, where each carrier may be a signal made up of multiplesub-carriers (e.g., waveform signals of different frequencies) modulatedaccording to the various radio technologies described above. Eachmodulated signal may be sent on a different sub-carrier and may carrycontrol information (e.g., reference signals, control channels, etc.),overhead information, user data, etc. The communication links 125 maytransmit bidirectional communications using frequency division duplex(FDD) (e.g., using paired spectrum resources) or time division duplex(TDD) operation (e.g., using unpaired spectrum resources). Framestructures for FDD (e.g., frame structure type 1) and TDD (e.g., framestructure type 2) may be defined.

In some examples of the system 100, base stations 105 or UEs 115 mayinclude multiple antennas for employing antenna diversity schemes toimprove communication quality and reliability between base stations 105and UEs 115. Additionally or alternatively, base stations 105 or UEs 115may employ multiple input multiple output (MIMO) techniques that maytake advantage of multi-path environments to transmit multiple spatiallayers carrying the same or different coded data.

Wireless communications system 100 may support operation on multiplecells or carriers, a feature which may be referred to as carrieraggregation (CA) or multi-carrier operation. A carrier may also bereferred to as a component carrier (CC), a layer, a channel, etc. Theterms “carrier,” “component carrier,” “cell,” and “channel” may be usedinterchangeably herein. A UE 115 may be configured with multipledownlink CCs and one or more uplink CCs for carrier aggregation. Carrieraggregation may be used with both FDD and TDD component carriers.

The term “component carrier” may refer to each of the multiple carriersutilized by a UE in CA operation, and may be distinct from otherportions of system bandwidth. For instance, a component carrier may be arelatively narrow-bandwidth carrier susceptible of being utilizedindependently or in combination with other component carriers. Eachcomponent carrier may provide the same capabilities as an isolatedcarrier based on Release 8 or Release 9 of the LTE standard, forinstance. Multiple component carriers may be aggregated or utilizedconcurrently to provide some UEs 115 with greater bandwidth and, e.g.,higher data rates. Thus, individual component carriers may be backwardscompatible with legacy UEs 115 while other UEs 115 may be configuredwith multiple component carriers in a multi-carrier mode.

A carrier used for DL may be referred to as a DL CC, and a carrier usedfor UL may be referred to as an UL CC. A UE 115 may be configured withmultiple DL CCs and one or more UL CCs for carrier aggregation. Eachcarrier may be used to transmit control information (e.g., referencesignals, control channels, etc.), overhead information, data, etc. A UE115 may communicate with a single base station 105 utilizing multiplecarriers, and may also communicate with multiple base stationssimultaneously on different carriers. Each cell of a base station 105may include an UL component carrier (CC) and a DL CC. The coverage area110 of each serving cell for a base station 105 may be different (e.g.,CCs on different frequency bands may experience different path loss).

In some examples, one carrier is designated as the primary carrier, orprimary component carrier (PCC), for a UE 115, which may be served by aprimary cell (PCell). Primary cells may be semi-statically configured byhigher layers (e.g., radio resource control (RRC), etc.) on a per-UEbasis. Certain uplink control information (UCI), and schedulinginformation transmitted on physical uplink control channel (PUCCH), arecarried by the primary cell. Additional carriers may be designated assecondary carriers, or secondary component carriers (SCC), which may beserved by secondary cells (SCells). Secondary cells may likewise besemi-statically configured on a per-UE basis. In some cases, secondarycells may not include or be configured to transmit the same controlinformation as the primary cell. In some examples, and as describedbelow, an enhanced component carrier (eCC) may be configured—e.g., as anSCell. An eCC may utilize nested system operation, which may bedynamically adjusted according to traffic conditions or latency needs ofUEs 115 within the system. In some examples, a UE 115 may be assignedresources of a first CC (e.g., SCC) utilizing frequency resources of asecond component carrier (e.g., PCC). For instance, one or more OFDMsymbols of a subframe of the second CC may be configured to signalcontrol information for resource segments of the first CC. Additionallyor alternatively, a UE 115 may utilize one CC to transmit controlinformation such as channel quality information (CQI), hybrid automaticrepeat request (HARD) feedback (e.g., ACK/NACK), etc. to the basestation 105. As described below, the resource segments of the first CCmay have a duration less than a symbol period of the second CC.

In some cases, a UE 115 may be served by cells from two or more basestations 105 that are connected by a non-ideal backhaul link 134 in dualconnectivity operation. For example, the connection between the servingbase stations 105 may not be sufficient to facilitate precise timingcoordination. Thus, in some cases, the cells serving a UE 115 may bedivided into multiple timing adjustment group (TAGs). Each TAG may beassociated with a different timing offset, such that the UE 115 maysynchronize UL transmissions differently for different UL carriers.

In some examples, one cell may utilize licensed spectrum, while anothercell may utilize unlicensed spectrum. An eCC may be configured forunlicensed spectrum, for instance. Broadly speaking, the unlicensedspectrum in some jurisdictions may range from 600 Megahertz (MHz) to 6Gigahertz (GHz). As used herein, the term “unlicensed spectrum” or“shared spectrum” may thus refer to industrial, scientific and medical(ISM) radio bands, irrespective of the frequency of those bands. In someexamples, unlicensed spectrum is the U-NII radio band, which may also bereferred to as the 5 GHz or 5G band. By contrast, the term “licensedspectrum” or “cellular spectrum” may be used herein to refer to wirelessspectrum utilized by wireless network operators under administrativelicense from a governing agency.

FIG. 2 is a diagram illustrating an example of a frame structure 200that may be used in a wireless communication system, including thewireless communication system 100 described above with reference to theFIG. 1. For example, the frame structure 200 may be used to supportnested system operation. A frame 210, which may have a 10 ms duration,may be divided into ten (10) equally sized subframes (e.g., subframe225, 230, 235, 240, 245, etc.).

An OFDMA component carrier (CC) 250 may be illustrated as a resourcegrid representing the two time slots 262, 264, each time slot includingseven OFDM symbols 266, for a normal cyclic prefix. Each OFDM symbol 266may have a duration defined as a symbol period. As discussed in furtherdetail below, each subframe 225, and thus one or both slots 262 or 264,may also include resource segments having a duration less than a symbolperiod. Accordingly, in some examples, CC 250 is an eCC configured tosupport low latency operations.

The resource grid may be divided into multiple resource elements 252. Aswith LTE/LTE-A systems, a resource block 256 may contain 12 consecutivesubcarriers 268 in the frequency domain and, for a normal cyclic prefixin each OFDM symbol 266, 7 consecutive OFDM symbols 266 in the timedomain, or 84 resource elements 252. The tone spacing for subcarriers268 may be 15 kHz, and a useful symbol duration for OFDM symbols 266 maybe 66.67 μs. OFDM symbols 266 may also include a cyclic prefix that is,for a normal LTE cyclic prefix, 5.1 μs for a first OFDM symbol 266 ineach slot 262, 264, or 4.69 μs for other OFDM symbols 266.

In some examples, one or more OFDM symbols 266 within the subframe 230structure may be divided into several resource segments having varyingdurations (as shown in FIG. 3). For instance, one resource segmenthaving a duration that is less than a symbol period may be configuredwithin subframe 225; and a second resource segment having a durationless than a symbol period may also be configured in subframe 225. Theseresource segments may have a total duration that is less than or equalto a symbol period. In some cases, one or both resource segments areconfigured with a cyclic prefix (CP). The subframe 225 may also have anOFDM symbol configured adjacent to the resource segments such that acontrol or data signal may be transmitted utilizing the symbol and theresource segments, where the signal duration spans the symbol period andthe durations of the resource segments.

As illustrated in FIG. 2, some of the resource elements, designated R(e.g., RS resource element 254), may include DL reference signals(DL-RS). In system 100 of FIG. 1, for instance, a base station 105 may,for example, insert periodic DL-RS, or pilot symbols, such as commonreference signals (CRS) to aid UEs 115 in channel estimation andcoherent demodulation. CRS may include one of 504 different cellidentities. They may be modulated using quadrature phase shift keying(QPSK) and power boosted (e.g., transmitted at 6 dB higher than thesurrounding data elements) to make them resilient to noise andinterference. CRS may be embedded in 4 to 16 resource elements, in eachresource block based on the number of antenna ports or layers (up to 4)of the receiving UEs 115. Additionally or alternatively, CRS may betransmitted utilizing resource segments, as described below. In someexamples, one or more subframes (e.g., 225, 230, 235, 240, 245) may beallocated for use by, and may thus have resources scheduled for, certainUEs 115, such as advanced UEs 115. In such instances, although noresources in the subframe may be scheduled for a legacy UE 115, a legacyUE 115 may nonetheless monitor the subframe for CRS. In some cases, inorder to minimize interference for legacy UEs 115, consistent OFDMnumerology (e.g., tone spacing, OFDM symbol, etc.) may be maintained tosupport communication for with both advanced UEs 115 and the legacy UEs115.

In addition to CRS, which may be utilized by all UEs 115 in the coveragearea 110 of the base station 105, demodulation reference signal (DMRS)may be directed toward specific UEs 115 and may be transmitted only onresource blocks, or resource segments, assigned to those UEs 115. DMRSmay include signals on 6 resource elements in each resource block inwhich they are transmitted. In other examples, DMRS may be transmittedon a single resource segment, or on multiple resource segments. In somecases, two sets of DMRS may be transmitted in adjoining resourceelements or in a combination of resource elements (e.g., symbols) andresource segments. In some cases, additional reference signals known aschannel state information (CSI) reference signals may be included to aidin generating CSI. On the UL, a UE 115 may transmit a combination ofperiodic sounding reference signals (SRS) and UL DMRS for linkadaptation and demodulation, respectively.

FIG. 3A is a block diagram 300 conceptually illustrating an example ofradio frame 305 that may be transmitted within a wireless communicationsystem, in accordance with an aspect of the present disclosure. Theradio frame 305 may be transmitted using portions of the wirelesscommunications system 100 described with reference to FIG. 1 between oneor more base stations 105 and one or more UEs 115, for example. Radioframe 305 may be a frame of an eCC, as described above. Radio frame 305may include ten (10) 1 ms subframes variously configured for uplink anddownlink communications, including downlink subframes 310, specialsubframes 315, uplink subframes 320, or adaptive subframe 323, or acombination thereof. The downlink subframes 310, special subframes 315,uplink subframes 320, and adaptive subframe 323 may include a subframestructure as discussed above with respect to FIG. 2, including fourteen(14) symbols 325 within each 1 ms subframe. In some examples, downlinksubframes 310 may include downlink OFDM symbols, uplink subframes 320may include SC-FDM symbols, and special subframes 315 and adaptivesubframes 323 may include both uplink SC-FDM symbols and downlink OFDMsymbols.

In some examples, certain subframes are configured with resourcesegments having a duration less than a symbol period. For instance,adaptive subframe 323 may include several OFDM symbols 325 that may befurther subdivided into resource segments 330, 335, 340, and 345.Although each segment may be of varying length (e.g., duration), thetotal duration of the resource segments 330, 335, 340 and 345 may equalthe symbol period of the OFDM symbols 325. Thus, a base station or UEmay utilize the resource segments 330, 335, 340, and 345 to transmit orreceive control or data signals, or both. In some examples, a control ordata signal may span some or all of a resource segment (e.g., segment345) and some or all of a symbol period of a symbol (e.g., OFDM symbol325). In some cases, a portion of the subframe 323 is allocated foradvanced UEs 115 (e.g., OFDM symbol 2), and the remaining portion of thesubframe (e.g., OFDM symbols 0-1 or 3-13) may be allocated to legacy UEs115. Additionally or alternatively, resource segments 330, 335, 340, 345may include cyclic prefixes 350 and 355.

Therefore, in some examples, certain UEs, such as advanced UEs, may beconfigured to communicate using resources configured as OFDM symbols(e.g., OFDM symbol 325) or resources subdivided into resource segments(e.g., resource segment 335), or both. This flexible resourceconfiguration may be utilized to support lower latency communication.For example, adaptive subframe 323 may be configured for time-divisionmultiplexing such that various resource segments or symbols may beutilized for uplink and downlink communications. Alternatively, adownlink subframe (e.g., subframe 310) may be configured with resourcesegments (e.g., resource segments 335, 340, or 345). These segments mayutilize wide-frequency bands and short durations, relative to a symbolperiod of an OFDM symbol 325, to provide downlink bursts. Uplinksubframes (e.g., subframe 320) may be similarly configured to utilizeresource segments.

In some examples, the duration of the one or more segments or OFDMnumerology design of such segments (e.g., tone spacing or OFDM symbollength) may be based on a number of factors, including, for example,delay spreads, Doppler shifts, or the like. Additionally, because theconfiguration of certain resource segments configured for advanced UEsmay affect resource allocation for legacy UEs, a duration of a resourcesegment may be defined with respect to legacy LTE system numerology.

An LTE OFDM symbol (e.g., 325) with a cyclic prefix may have a symbolperiod (e.g., a duration) of 71.4 μs (e.g., 66.67 μs OFDM symbol with4.76 μs CP). Thus, in some cases, 71.4 μs may represent a durationwithin which resource segments may need to be synchronized foroperation. For instance, if a resource segment is 16.67 μs in duration,four (4) such segments may be configured within an LTE symbol period,leaving 1.2 μs for a cyclic prefix, which may be too short in somecases. Alternatively, if three (3) resource segments of 16.67 μs areconfigured within an LTE symbol period, a cyclic prefix may be 7.1 μs,which may be too long in some cases. Accordingly, in some examples,three (3) 16.67 μs resource segments and one (1) 8.33 μs resourcesegment may be configured within an LTE symbol period, allowing for acyclic prefix length of 3.27 μs, which may be preferable in somescenarios.

In other examples, resource segments may be configured within a durationof several LTE symbols. For instance, seven (7) 16.67 μs resourcesegments with a cyclic prefix of 3.73 μs may be configured within theduration of two (2) LTE symbols. The resource segments may thus not bedivided evenly by LTE symbol period, but such a configuration may stillsupport backward compatibility with proper resource allocation. Forinstance, if OFDM symbols 2 and 3 of adaptive subframe 323 areconfigured with resource segments as described, those two symbols maynot be allocated to legacy UEs, but symbols 0, 1, and 4-13 may still beutilized by legacy UEs.

In some examples, one or more adaptive subframes 323 may beMulticast-broadcast single-frequency network (MBSFN) subframes used toprovide multimedia multicast or broadcast services to certain UEs 115.The configuration of such subframes may be signaled to both advanced andlegacy UEs within a system, for instance, in PBCH. A legacy UE 115 maynot monitor the MBSFN portion of the MBSFN subframe, and thus may notattempt to decode the MBSFN portion, because the legacy UE may not becapable of receiving multicast or broadcast service, for example. As aresult, the resources of the MBSFN portion of a an MBSFN subframe may beallocated to advanced UEs 115 without adversely impacting legacy UEs,because the legacy UE may not attempt to decode such information.Accordingly, in a system employing multicast-broadcast services, unusedMBSFN subframes, or portions of MBSFN subframes, may be configured withresource segments have a duration less than an LTE symbol period. Thisconfiguration may provide for ready backward compatibility with legacyUEs.

FIG. 3B is a block diagram 302 conceptually illustrating an example ofradio frames 305-a and 360 that may be transmitted within a wirelesscommunication system, in accordance with an aspect of the presentdisclosure. The radio frames 305-a or 360 may be transmitted usingportions of the wireless communications system 100 described withreference to FIG. 1 between one or more base stations 105 and one ormore UEs 115, for example. Radio frame 305-a may be a frame of an eCC,as described above, and may be an example of radio frame 305 describedabove with reference to FIG. 3A.

As discussed above, radio frame 305-a may include ten (10) 1 mssubframes variously configured for uplink and downlink communications,including downlink subframes 310-a, special subframes 315-a, uplinksubframes 320-a, or adaptive subframe 323-a, or a combination thereof.One or more adaptive subframes may include a subframe structure asdiscussed above with respect to FIG. 2, including fourteen (14) symbols325 within each 1 ms subframe, which may be further configured with anumber of resource segments.

Radio frame 360 may be a frame of another component carrier, which maybe a PCC, for a UE 115. Radio frame 360 may also include a number ofsubframes (e.g., subframe 365), and may be further divided into symbolperiods—e.g., a subframe 365 may have fourteen (14) OFDM symbols withineach 1 ms subframe. Some of the OFDM symbols of a subframe may includecontrol information, and may be referred to as a control region 370 andthe remaining symbols may include or be allocated for data, and may bereferred to as a data region 372). In some examples, OFDM symbols 375(or a portion of an OFDM symbol) of the radio frame 360 of (e.g., aradio frame of one CC) may be utilized to schedule resources of theradio frame 305-a (e.g., a radio frame of an eCC). This cross-carrierscheduling may be performed utilizing, in some examples, resources of adata region 372 of a subframe 365. Thus, frequency resources of one CCmay be utilized to schedule frequency resources of one or severalresource segments 330-a or 335-a of adaptive subframe 323 of another CC.Additionally or alternatively, feedback related to the resource segments330-a or 335-a (e.g., CQI, ACK/NACK, etc.) may be transmitted (andreceived) on frequency resources of the radio frame 360 (e.g., OFDMsymbol 375).

The time lines of radio frames 305-a and 360 may be synchronized. Forinstance, a resource segment 330-a may be synchronized with a symbolperiod of an OFDM symbol 375. In some examples, the resource segments330-a and 335-a are synchronized with several symbol periods of subframe365. This synchronization may support cross-carrier scheduling, asdescribed above, thus allowing a subset of resources of the radio frame360 to be used for control of a subset of resources of radio frame305-a. This may apply for uplink control signaling or downlink controlsignaling, or both.

As mentioned, reference signals—e.g., DMRS, CRS, CSI reference signals,etc. or measurement reference signals—may be transmitted in one or moresegments 330, 335, 340, or 345, or may span the entire period of an OFDMsymbol 325, of FIG. 3A or 3B. 325-a.

FIGS. 4A, 4B, and 4C are diagrams illustrating example subframestructures 400, 402, and 404, respectively, and various reference signalconfigurations that may be used in a wireless communication system,including the wireless communication system 100 described above withreference to FIG. 1. For example, the subframe structures 400, 402, and404 may be used for a nested system configuration. Subframe structures400, 402, and 404 may, for instance, be examples of subframes describedwith reference to FIG. 2 or 3.

In accordance with the present disclosure, subframe structures 400, 402,and 404 may include one or several resource segments 405, 410 of varyingdurations, as well as several symbols having a symbol period (e.g.,symbol 325-a illustrated in FIG. 3). In some examples, a resourcesegment may span an OFDM symbol period (e.g., a resource segment 405 maybe equivalent to an OFDM symbol). Additionally or alternatively,subframe structures 400, 402, and 404 may include resource segments 410having duration that is less than a regular OFDM symbol period.

The resource segments may be configured to include DMRS, CRS, CSIreference signals, or the like. For example, as illustrated in FIG. 4A,reference signals may be transmitted in an OFDM symbol having a symbolperiod (e.g., 405-a through 405-c). In some examples, reference signalsmay be transmitted over one or several resource segments 410-a through410-c, as illustrated in FIG. 4B. In other examples, one or morereference signals may span a several resource segments 415-a of asubframe 404, as illustrated in FIG. 4C. In other words, a referencesignal may be transmitted within a symbol, over several symbols, withina single resource segment, over several resource segments, or over acombination of symbols and resource segments. In various examples, thisflexibility in reference signal assignment may allow either legacy UEsor non-legacy UEs, or both, to utilize reference signals transmittedwithin a subframe structure 400, 402, 404.

FIG. 5 shows a block diagram of a wireless device 500 that supportsnested system operation in accordance with various aspects of thepresent disclosure. Wireless device 500 may be an example of aspects ofa UE 115 or base station 105 described with reference to FIGS. 1-4.Wireless device 500 may include a receiver 505, a symbol adaptationmodule 510, or a transmitter 515. Wireless device 500 may also include aprocessor. Each of these components may be in communication with oneanother.

The receiver 505 may receive information such as packets, user data, orcontrol information associated with various information channels—e.g.,control channels, data channels, and information related to nestedsystem operation, etc. Information may be passed on to the symboladaptation module 510, and to other components of wireless device 500.

The symbol adaptation module 510 may configure a first resource segmenthaving a first duration that is less than a symbol period, and it mayconfigure a second resource segment having a second duration that isless than the symbol period. A total duration of the first and seconddurations may, for example, be less than or equal to the symbol period,and communicate utilizing the configured first and second resourcesegments.

The transmitter 515 may transmit signals received from other componentsof wireless device 500. In some examples, the transmitter 515 may becollocated with the receiver 505 in a transceiver. The transmitter 515may include a single antenna, or it may include a plurality of antennas.

FIG. 6 shows a block diagram of a wireless device 600 that supportsnested system operation in accordance with various aspects of thepresent disclosure. Wireless device 600 may be an example of aspects ofa wireless device 500, a UE 115, or base station 105 described withreference to FIGS. 1-5. Wireless device 600 may include a receiver505-a, a symbol adaptation module 510-a, or a transmitter 515-a.Wireless device 600 may also include a processor. Each of thesecomponents may be in communication with one another. The symboladaptation module 510-a may also include a symbol segment module 605,and a communication management module 610.

The receiver 505-a may receive information which may be passed on tosymbol adaptation module 510-a, and to other components of a UE 115 orbase station 105. The symbol adaptation module 510-a may perform theoperations described above with reference to FIG. 5. The transmitter515-a may transmit signals received from other components of wirelessdevice 600.

The symbol segment module 605 may configure a first resource segmenthaving a first duration that is less than a symbol period as describedabove with reference to FIGS. 2-4. The symbol segment module 605 mayalso configure a second resource segment having a second duration thatis less than the symbol period, such that a total duration of the firstand second durations is less than or equal to the symbol period. In someexamples, the first resource segment may be configured to utilize thefirst resource segment module 615. Similarly, the second resourcesegment may be configured utilizing the second resource segment module620. In some examples, the first resource segment may include a firstCP, and the second resource segment may include a second CP. The symbolsegment module 605 may also configure a third resource segment having athird duration that is less than the symbol period, such that a totalduration of the first, second, and third durations is greater than thesymbol period. The third resource segment may be configured utilizingthe third resource segment module 625.

In some examples, the symbol segment module 605 may also identify afirst resource segment having a first duration that is less than asymbol period. The symbol segment module 605 may also identify a secondresource segment having a second duration that is less than the symbolperiod, where a total duration of the first and second durations is lessthan or equal to the symbol period. The symbol segment module 605 mayalso identify a third resource segment having a third duration that isless than the symbol period, where a total duration of the first,second, and third durations is greater than the symbol period.

The communication management module 610 may communicate utilizing theconfigured first and second resource segments as described above withreference to FIGS. 2-4. In some examples, communicating may includecommunicating utilizing the configured symbol, the configured firstresource segment, the configured second resource segment, or combinationthereof in a common subframe.

In some examples, communicating may include transmitting a control ordata signal in the first resource segment, the second resource segment,and a symbol having the symbol period. The control or data signal maythus span the first and second durations and the symbol period.

The communication management module 610 may also communicate utilizingthe configured first, second, and third resource segments. In someexamples, communicating includes transmitting a control or data signalin the first resource segment, the second resource segment, and thethird resource segment, and the control or data signal may span thefirst, second, and third durations. The communication management module610 may also communicate with a node utilizing the first and secondresource segments. In some examples, communicating with the nodeincludes communicating utilizing the symbol and the first and secondresource segments in a common subframe.

In some examples, communicating with the node includes receiving acontrol or data signal in the first resource segment, the secondresource segment, and a symbol having the symbol period. The control ordata signal may thus span the first and second durations and the symbolperiod. The communication management module 610 may also communicateutilizing the first, second, and third resource segments. In someexamples, communicating with the node includes receiving a control ordata signal in the first resource segment, the second resource segment,and the third resource segments, where the control or data signal spansthe first, second, and third durations.

In some examples, first and second resource segments may be frequencyresources of a first component carrier. The communication managementmodule 610 may thus schedule the frequency resources of the firstcomponent carrier using frequency resources of a second componentcarrier. In some cases, the receiver 505-a, in combination with thecommunication management module may receive feedback related to thefirst or second resource segments on the frequency resources of thesecond component carrier. Alternatively, the receiver 505-a, incombination with the communication management module 610, may receivegrants for the frequency resources of the first component carrier onfrequency resources of a second component carrier. In some examples, thetransmitter 515-a may transmit feedback related to the first or secondresource segments on the frequency resources of the second componentcarrier.

FIG. 7 shows a block diagram 700 of a symbol adaptation module 510-bwhich may be a component of a wireless device 500 or a wireless device600 that support nested system operation in accordance with variousaspects of the present disclosure. The symbol adaptation module 510-bmay be an example of aspects of a symbol adaptation module 510 describedwith reference to FIGS. 5-6. The symbol adaptation module 510-b mayinclude a symbol segment module 605-a, and a communication managementmodule 610-a. Each of these modules may perform the functions describedabove with reference to FIG. 6. The symbol adaptation module 510-b mayalso include a symbol configuration module 705, a RS assignment module710, and a symbol identification module 715.

The symbol configuration module 705 may configure a symbol having thesymbol period, where communicating with the wireless device includescommunicating utilizing the configured symbol the configured first andsecond resource segments as described above with reference to FIGS. 2-4.

The RS assignment module 710 may be configured such that the firstresource segment, the second resource segment, or a combination thereofmay include a DMRS as described above with reference to FIGS. 2-4. Insome examples, a symbol includes a portion of the DMRS, where the symbolhas a duration of the symbol period, and where the DMRS spans the firstand second durations and the symbol period. In some examples, the firstresource segment, the second resource segment, or combination thereofmay include a CRS. A symbol may thus include a portion of the CRS, wherethe symbol has a duration of the symbol period, and where the CRS spansthe first and second durations and the symbol period. In some examples,the first resource segment, the second resource segment, or combinationthereof include a CSI reference signal. In some examples, a resource,such as a symbol, includes a portion of the CSI reference signal, wherethe symbol has a duration of the symbol period, and where the CSIreference signal spans the first and second durations and the symbolperiod.

The symbol identification module 715 may identify a symbol having thesymbol period, such that communicating may include communicatingutilizing the symbol and the first and second resource segments asdescribed above with reference to FIGS. 2-4.

The components of wireless device 500, wireless device 600, or symboladaptation module 510-b may each, individually or collectively, beimplemented with at least one application specific integrated circuit(ASIC) adapted to perform some or all of the applicable functions inhardware. Alternatively, the functions may be performed by one or moreother processing units (or cores), on at least one IC. In other examplesother types of integrated circuits may be used (e.g.,Structured/Platform ASICs, a field programmable gate array (FPGA), oranother semi-custom IC), which may be programmed in any manner known inthe art. The functions of each unit may also be implemented, in whole orin part, with instructions embodied in a memory, formatted to beexecuted by one or more general or application-specific processors.

FIG. 8 shows a diagram of a system 800 including a UE 115 that supportsnested system operation in accordance with various aspects of thepresent disclosure. System 800 may include UE 115-a, which may be anexample of a wireless device 500 or a wireless device 600, describedabove with reference to FIGS. 1 and 5-7. UE 115-a may include a symboladaptation module 810, which may be an example of a symbol adaptationmodule 510 described with reference to FIGS. 5-7. UE 115-a may alsoinclude an RS identification module 825. UE 115-a may also includecomponents for bi-directional voice and data communications includingcomponents for transmitting communications and components for receivingcommunications. For example, UE 115-a may communicate bi-directionallywith base station 105-a or UE 115-b. UE 115-a may be an example of anon-legacy UE.

The RS identification module 825 may be configured such that the firstresource segment, the second resource segment, or combination thereofmay include a DMRS as described above with reference to FIGS. 2-4. Insome examples, a symbol includes a portion of the DMRS, the symbolhaving the symbol period, and where the DMRS spans the first and seconddurations and the symbol period. In some examples, the first resourcesegment, the second resource segment, or combination thereof includes aCRS. In some examples, a symbol includes a portion of the CRS, thesymbol having the symbol period, and where the CRS spans the first andsecond durations and the symbol period. In some examples, the firstresource segment, the second resource segment, or combination thereofincludes a CSI reference signal. In some examples, a symbol includes aportion of the CSI reference signal, the symbol having the symbolperiod, and where the CSI reference signal spans the first and seconddurations and the symbol period.

UE 115-a may also include a processor 805, and memory 815 (includingsoftware (SW) 820), a transceiver 835, and one or more antenna(s) 840,each of which may communicate, directly or indirectly, with one another(e.g., via bus or buses 845). The transceiver 835 may communicatebi-directionally, via the antenna(s) 840 or wired or wireless links,with one or more networks, as described above. For example, thetransceiver 835 may communicate bi-directionally with a base station 105or another UE 115. The transceiver 835 may include a modem to modulatethe packets and provide the modulated packets to the antenna(s) 840 fortransmission, and to demodulate packets received from the antenna(s)840. While UE 115-a may include a single antenna 840, UE 115-a may alsohave multiple antennas 840 capable of concurrently transmitting orreceiving multiple wireless transmissions.

The memory 815 may include random access memory (RAM) and read onlymemory (ROM). The memory 815 may store computer-readable,computer-executable software/firmware code 820 including instructionsthat, when executed, cause the processor 805 to perform or cause UE115-a to perform various functions described herein (e.g., nested systemoperation, etc.). Alternatively, the software/firmware code 820 may notbe directly executable by the processor 805 but cause a computer (e.g.,when compiled and executed) to perform functions described herein. Theprocessor 805 may include an intelligent hardware device, (e.g., acentral processing unit (CPU), a microcontroller, an ASIC, etc.).

FIG. 9 shows a diagram of a system 900 including a base station 105 thatsupports nested system operation in accordance with various aspects ofthe present disclosure. System 900 may include base station 105-b, whichmay be an example of a wireless device 500, a wireless device 600, asymbol adaptation module 510-b, or a base station 105 described abovewith reference to FIGS. 1 and 5-7. Base Station 105-b may include a basestation symbol adaptation module 910, which may be an example of a basestation symbol adaptation module 910 described with reference to FIGS.6-8. Base Station 105-b may also include components for bi-directionalvoice and data communications including components for transmittingcommunications and components for receiving communications. In someexamples, the base station 105-b may also include a reference signalidentification module 945.

In some cases, base station 105-b may have one or more wired backhaullinks. Base station 105-b may have a wired backhaul link (e.g., S1interface, etc.) to the core network 130. Base station 105-b may alsocommunicate with other base stations 105, such as base station 105-c andbase station 105-d via inter-base station backhaul links (e.g., an X2interface). Each of the base stations 105 may communicate with UEs 115using the same or different wireless communications technologies. Insome cases, base station 105-b may communicate with other base stationssuch as 105-c or 105-d utilizing base station communications module 925.In some examples, base station communications module 925 may provide anX2 interface within an LTE/LTE-A wireless communication networktechnology to provide communication between some of the base stations105. In some embodiments, base station 105-b may communicate with otherbase stations through core network 130. In some cases, base station105-b may communicate with the core network 130 through networkcommunications module 930.

The base station 105-b may include a processor 905, memory 915(including software (SW) 920), transceiver 935, and antenna(s) 940,which each may be in communication, directly or indirectly, with oneanother (e.g., over bus or buses 947). The transceiver 935 may beconfigured to communicate bi-directionally, via the antenna(s) 940, withthe UEs 115, which may be multi-mode devices. The transceiver 935 (orother components of the base station 105-b) may also be configured tocommunicate bi-directionally, via the antennas 940, with one or moreother base stations (not shown). The transceiver 935 may include a modemconfigured to modulate the packets and provide the modulated packets tothe antennas 940 for transmission, and to demodulate packets receivedfrom the antennas 940. The base station 105-b may include multipletransceiver 935, each with one or more associated antennas 940. Thetransceiver 935 may be an example of a combined receiver 505 andtransmitter 515 of FIG. 5.

The memory 915 may include RAM and ROM. The memory 915 may also storecomputer-readable, computer-executable software code 920 containinginstructions that are configured to, when executed, cause the processor905 to perform or cause base station 105-b to perform various functionsdescribed herein (e.g., nested system operation, etc.). Alternatively,the software code 920 may not be directly executable by the processor905 but be configured to cause the computer, e.g., when compiled andexecuted, to perform functions described herein. The processor 905 mayinclude an intelligent hardware device, e.g., a CPU, a microcontroller,an ASIC, etc. The processor 905 may include various special purposeprocessors such as encoders, queue processing modules, base bandprocessors, radio head controllers, digital signal processor (DSPs), andthe like. The base station communications module 925 may managecommunications with other base stations 105. The communicationsmanagement module may include a controller or scheduler for controllingcommunications with UEs 115 in cooperation with other base stations 105.For example, the base station communications module 925 may coordinatescheduling for transmissions to UEs 115 for various interferencemitigation techniques such as beamforming or joint transmission.

The RS identification module 945 may be configured such that the firstresource segment, the second resource segment, or combination thereofmay include a DMRS as described above with reference to FIGS. 2-4. Insome examples, a symbol includes a portion of the DMRS, the symbolhaving the symbol period, and where the DMRS spans the first and seconddurations and the symbol period. In some examples, the first resourcesegment, the second resource segment, or combination thereof includes aCRS. In some examples, a symbol includes a portion of the CRS, thesymbol having the symbol period, and where the CRS spans the first andsecond durations and the symbol period. In some examples, the firstresource segment, the second resource segment, or combination thereofincludes a CSI reference signal. In some examples, a symbol includes aportion of the CSI reference signal, the symbol having the symbolperiod, and where the CSI reference signal spans the first and seconddurations and the symbol period.

FIG. 10 shows a flowchart illustrating a method 1000 for wirelesscommunication that supports nested system operation in accordance withvarious aspects of the present disclosure. The operations of method 1000may be implemented by a UE 115 or base station 105 or its components asdescribed with reference to FIGS. 1-9. For example, the operations ofmethod 1000 may be performed by the symbol adaptation module 510, symboladaptation module 810, or base station symbol adaptation module 910, asdescribed with reference to FIGS. 5-9. In some examples, a device (e.g.,base station 105 or UE 115) may execute a set of codes to control thefunctional elements to perform the functions described below.Additionally or alternatively, the device may perform aspects thefunctions described below using special-purpose hardware.

At block 1005, the device may configure a first resource segment havinga first duration that is less than a symbol period as described abovewith reference to FIGS. 2-4. In certain examples, the operations ofblock 1005 may be performed by the symbol segment module 605 asdescribed above with reference to FIG. 6.

At block 1010, the device may configure a second resource segment havinga second duration that is less than the symbol period, where a totalduration of the first and second durations is less than or equal to thesymbol period as described above with reference to FIGS. 2-4. In certainexamples, the operations of block 1010 may be performed by the symbolsegment module 605 as described above with reference to FIG. 6.

At block 1015, the device may communicate utilizing the configured firstand second resource segments as described above with reference to FIGS.2-4. In certain examples, the operations of block 1015 may be performedby the communication management module 610 as described above withreference to FIG. 6.

FIG. 11 shows a flowchart illustrating a method 1100 for wirelesscommunication that supports nested system operation in accordance withvarious aspects of the present disclosure. The operations of method 1100may be implemented by a UE 115, base station 105 or its components asdescribed with reference to FIGS. 1-9. For example, the operations ofmethod 1100 may be performed by the symbol adaptation module 510, symboladaptation module 810, or base station symbol adaptation module 910, asdescribed with reference to FIGS. 5-9. In some examples, a device (e.g.,base station 105 or UE 115) may execute a set of codes to control thefunctional elements of the device to perform the functions describedbelow. Additionally or alternatively, the device may perform aspects thefunctions described below using special-purpose hardware. The method1100 may also incorporate aspects of method 1000 of FIG. 10.

At block 1105, the device may configure a first resource segment havinga first duration that is less than a symbol period as described abovewith reference to FIGS. 2-4. In certain examples, the operations ofblock 1105 may be performed by the symbol segment module 605 asdescribed above with reference to FIG. 6.

At block 1110, the device may configure a second resource segment havinga second duration that is less than the symbol period, where a totalduration of the first and second durations is less than or equal to thesymbol period as described above with reference to FIGS. 2-4. In certainexamples, the operations of block 1110 may be performed by the symbolsegment module 605 as described above with reference to FIG. 6.

At block 1115, the device may configure a symbol having the symbolperiod. In certain examples, the operations of block 1115 may beperformed by the symbol configuration module 705 as described above withreference to FIG. 7.

At block 1120, the device may communicate utilizing the configuredsymbol, the configured first and second resource segments, orcombination thereof as described above with reference to FIGS. 2-4. Incertain examples, the operations of block 1120 may be performed by thecommunication management module 610 as described above with reference toFIG. 6. In some examples, the first and second resource segments includefrequency resources of a first component carrier, and the device mayschedule the frequency resources of the first component carrierutilizing resources of a second component carrier. Additionally oralternatively, the device may receive feedback related to the first orsecond resource segments on the frequency resources of the secondcomponent carrier.

FIG. 12 shows a flowchart illustrating a method 1200 for wirelesscommunication that supports nested system operation in accordance withvarious aspects of the present disclosure. The operations of method 1200may be implemented by a UE 115, base station 105 or its components asdescribed with reference to FIGS. 1-9. For example, the operations ofmethod 1200 may be performed by the symbol adaptation module 510, symboladaptation module 810, or base station symbol adaptation module 910, asdescribed with reference to FIGS. 5-9. In some examples, a device (e.g.,base station 105 or UE 115) may execute a set of codes to control thefunctional elements to perform the functions described below.Additionally or alternatively, the device may perform aspects thefunctions described below using special-purpose hardware. The method1200 may also incorporate aspects of methods 1000 and 1100 of FIGS.10-11.

At block 1205, the device may configure a first resource segment havinga first duration that is less than a symbol period as described abovewith reference to FIGS. 2-4. In certain examples, the operations ofblock 1205 may be performed by the symbol segment module 605 asdescribed above with reference to FIG. 6.

At block 1210, the device may configure a second resource segment havinga second duration that is less than the symbol period, where a totalduration of the first and second durations is less than or equal to thesymbol period as described above with reference to FIGS. 2-4. In certainexamples, the operations of block 1210 may be performed by the symbolsegment module 605 as described above with reference to FIG. 6.

At block 1215, the device may configure a third resource segment havinga third duration that is less than the symbol period, where a totalduration of the first, second, and third durations is greater than thesymbol period as described above with reference to FIGS. 2-4. In certainexamples, the operations of block 1215 may be performed by the symbolsegment module 605 as described above with reference to FIG. 6.

At block 1220, the device may communicate utilizing the configuredfirst, second, and third resource segments as described above withreference to FIGS. 2-4. In certain examples, the operations of block1220 may be performed by the communication management module 610 asdescribed above with reference to FIG. 6.

FIG. 13 shows a flowchart illustrating a method 1300 for wirelesscommunication that supports nested system operation in accordance withvarious aspects of the present disclosure. The operations of method 1300may be implemented by a UE 115, base station 105 or its components asdescribed with reference to FIGS. 1-9. For example, the operations ofmethod 1300 may be performed by the symbol adaptation module 510, symboladaptation module 810, or base station symbol adaptation module 910, asdescribed with reference to FIGS. 5-9. In some examples, a device (e.g.,base station 105 or UE 115) may execute a set of codes to control thefunctional elements to perform the functions described below.Additionally or alternatively, the device may perform aspects thefunctions described below using special-purpose hardware. The method1300 may also incorporate aspects of methods 1000, 1100, and 1200 ofFIGS. 10-12.

At block 1305, the device may identify a first resource segment having afirst duration that is less than a symbol period as described above withreference to FIGS. 2-4. In certain examples, the operations of block1305 may be performed by the symbol segment module 605 as describedabove with reference to FIG. 6.

At block 1310, the device may identify a second resource segment havinga second duration that is less than the symbol period, where a totalduration of the first and second durations is less than or equal to thesymbol period as described above with reference to FIGS. 2-4. In certainexamples, the operations of block 1310 may be performed by the symbolsegment module 605 as described above with reference to FIG. 6.

At block 1315, the device may communicate with a node utilizing thefirst and second resource segments as described above with reference toFIGS. 2-4. In certain examples, the operations of block 1315 may beperformed by the communication management module 610 as described abovewith reference to FIG. 6.

FIG. 14 shows a flowchart illustrating a method 1400 for wirelesscommunication that supports nested system operation in accordance withvarious aspects of the present disclosure. The operations of method 1400may be implemented by a UE 115, base station 105 or its components asdescribed with reference to FIGS. 1-9. For example, the operations ofmethod 1400 may be performed by the symbol adaptation module 510, symboladaptation module 810, or base station symbol adaptation module 910, asdescribed with reference to FIGS. 5-9. In some examples, a device (e.g.,base station 105 or UE 115) may execute a set of codes to control thefunctional elements to perform the functions described below.Additionally or alternatively, the device may perform aspects thefunctions described below using special-purpose hardware. The method1400 may also incorporate aspects of methods 1000, 1100, 1200, and 1300of FIGS. 10-13.

At block 1405, the device may identify a first resource segment having afirst duration that is less than a symbol period as described above withreference to FIGS. 2-4. In certain examples, the operations of block1405 may be performed by the symbol segment module 605 as describedabove with reference to FIG. 6.

At block 1410, the device may identify a second resource segment havinga second duration that is less than the symbol period, where a totalduration of the first and second durations is less than or equal to thesymbol period as described above with reference to FIGS. 2-4. In certainexamples, the operations of block 1410 may be performed by the symbolsegment module 605 as described above with reference to FIG. 6.

At block 1415, the device may identify a symbol having the symbol periodas described above with reference to FIGS. 2-4. In certain examples, theoperations of block 1415 may be performed by the symbol identificationmodule 715 as described above with reference to FIG. 7.

At block 1420, the device may communicate with a node utilizing thesymbol, first resource segment, second resource segment, or combinationthereof as described above with reference to FIGS. 2-4. In certainexamples, the operations of block 1420 may be performed by thecommunication management module 610 as described above with reference toFIG. 6. In some examples, the first and second resource segments includefrequency resources of a first component carrier, and the device mayreceive grants for the frequency resources of the first componentcarrier on resources of a second component carrier. Additionally oralternatively, the device may transmit feedback related to the first orsecond resource segments on the frequency resources of the secondcomponent carrier.

FIG. 15 shows a flowchart illustrating a method 1500 for wirelesscommunication that supports nested system operation in accordance withvarious aspects of the present disclosure. The operations of method 1500may be implemented by a UE 115, base station 105, or its components asdescribed with reference to FIGS. 1-9. For example, the operations ofmethod 1500 may be performed by the symbol adaptation module 510, symboladaptation module 810, or base station symbol adaptation module 910, asdescribed with reference to FIGS. 5-9. In some examples, a device (e.g.,base station 105 or UE 115) may execute a set of codes to control thefunctional elements to perform the functions described below.Additionally or alternatively, the device may perform aspects thefunctions described below using special-purpose hardware. The method1500 may also incorporate aspects of methods 1000, 1100, 1200, 1300, and1400 of FIGS. 10-14.

At block 1505, the device may identify a first resource segment having afirst duration that is less than a symbol period as described above withreference to FIGS. 2-4. In certain examples, the operations of block1505 may be performed by the symbol segment module 605 as describedabove with reference to FIG. 6.

At block 1510, the device may identify a second resource segment havinga second duration that is less than the symbol period, where a totalduration of the first and second durations is less than or equal to thesymbol period as described above with reference to FIGS. 2-4. In certainexamples, the operations of block 1510 may be performed by the symbolsegment module 605 as described above with reference to FIG. 6.

At block 1515, the device may identify a third resource segment having athird duration that is less than the symbol period, where a totalduration of the first, second, and third durations is greater than thesymbol period as described above with reference to FIGS. 2-4. In certainexamples, the operations of block 1515 may be performed by the symbolsegment module 605 as described above with reference to FIG. 6.

At block 1520, the device may communicate utilizing the first, second,and third resource segments as described above with reference to FIGS.2-4. In certain examples, the operations of block 1520 may be performedby the communication management module 610 as described above withreference to FIG. 6.

Thus, methods 1000, 1100, 1200, 1300, 1400, and 1500 may provide fornested system operation. It should be noted that methods 1000, 1100,1200, 1300, 1400, and 1500 describe possible implementation, and thatthe operations and the steps may be rearranged or otherwise modifiedsuch that other implementations are possible. In some examples, aspectsfrom two or more of the methods 1000, 1100, 1200, 1300, 1400, and 1500may be combined.

The detailed description set forth above in connection with the appendeddrawings describes example embodiments and does not represent all theembodiments that may be implemented or that are within the scope of theclaims. The term “exemplary” used throughout this description means“serving as an example, instance, or illustration,” and not “preferred”or “advantageous over other embodiments.” The detailed descriptionincludes specific details for the purpose of providing an understandingof the described techniques. These techniques, however, may be practicedwithout these specific details. In some instances, well-known structuresand devices are shown in block diagram form in order to avoid obscuringthe concepts of the described embodiments.

Information and signals may be represented using any of a variety ofdifferent technologies and techniques. For example, data, instructions,commands, information, signals, bits, symbols, and chips that may bereferenced throughout the above description may be represented byvoltages, currents, electromagnetic waves, magnetic fields or particles,optical fields or particles, or any combination thereof.

The various illustrative blocks and modules described in connection withthe disclosure herein may be implemented or performed with ageneral-purpose processor, a DSP, an ASIC, an FPGA or other programmablelogic device, discrete gate or transistor logic, discrete hardwarecomponents, or any combination thereof designed to perform the functionsdescribed herein. A general-purpose processor may be a microprocessor,but in the alternative, the processor may be any conventional processor,controller, microcontroller, or state machine. A processor may also beimplemented as a combination of computing devices (e.g., a combinationof a DSP and a microprocessor, multiple microprocessors, one or moremicroprocessors in conjunction with a DSP core, or any other suchconfiguration).

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope and spirit of the disclosure and appended claims. For example,due to the nature of software, functions described above can beimplemented using software executed by a processor, hardware, firmware,hardwiring, or combinations of any of these. Features implementingfunctions may also be physically located at various positions, includingbeing distributed such that portions of functions are implemented atdifferent physical locations. As used herein, including in the claims,the term “and/or,” when used in a list of two or more items, means thatany one of the listed items can be employed by itself or any combinationof two or more of the listed items can be employed. For example, if acomposition is described as containing components A, B, and/or C, thecomposition can contain A alone; B alone; C alone; A and B incombination; A and C in combination; B and C in combination; or A, B,and C in combination. Also, as used herein, including in the claims,“or” as used in a list of items (for example, a list of items prefacedby a phrase such as “at least one of” or “one or more of”) indicates adisjunctive list such that, for example, a list of “at least one of A,B, or C” means A or B or C or AB or AC or BC or ABC (i.e., A and B andC).

Computer-readable media includes both computer storage media andcommunication media including any medium that facilitates transfer of acomputer program from one place to another. A storage medium may be anyavailable medium that can be accessed by a general purpose or specialpurpose computer. By way of example, and not limitation,computer-readable media can comprise RAM, ROM, EEPROM, flash memory,CD-ROM or other optical disk storage, magnetic disk storage or othermagnetic storage devices, or any other medium that can be used to carryor store desired program code means in the form of instructions or datastructures and that can be accessed by a general-purpose orspecial-purpose computer, or a general-purpose or special-purposeprocessor. Also, any connection is properly termed a computer-readablemedium. For example, if the software is transmitted from a website,server, or other remote source using a coaxial cable, fiber optic cable,twisted pair, digital subscriber line (DSL), or wireless technologiessuch as infrared, radio, and microwave, then the coaxial cable, fiberoptic cable, twisted pair, DSL, or wireless technologies such asinfrared, radio, and microwave are included in the definition of medium.Disk and disc, as used herein, include compact disc (CD), laser disc,optical disc, digital versatile disc (DVD), floppy disk, and Blu-raydisc where disks usually reproduce data magnetically, while discsreproduce data optically with lasers. Combinations of the above are alsoincluded within the scope of computer-readable media.

The previous description of the disclosure is provided to enable aperson skilled in the art to make or use the disclosure. Variousmodifications to the disclosure will be readily apparent to thoseskilled in the art, and the generic principles defined herein may beapplied to other variations without departing from the scope of thedisclosure. Thus, the disclosure is not to be limited to the examplesand designs described herein but is to be accorded the broadest scopeconsistent with the principles and novel features disclosed herein.

What is claimed is:
 1. A method for wireless communication at a userequipment (UE), comprising: receiving, in a first subframe of a firstcomponent carrier from a node, a first symbol on a first resourcesegment, the first symbol having a first symbol period in a time domain;determining, based at least in part on information in the first symbol,that a second resource segment for communicating a second symbol isscheduled on a second component carrier, the second symbol having asecond symbol period in the time domain that is less than the firstsymbol period, the first symbol having a first tone spacing for one ormore subcarriers different from a second tone spacing for one or moresubcarriers of the second symbol; and communicating with the nodeutilizing the second symbol in the second resource segment in a secondsubframe.
 2. The method of claim 1, further comprising: determining,based at least in part on information in the first symbol, that a thirdresource segment for communicating a third symbol is scheduled on thesecond component carrier, the third symbol having a third symbol periodin the time domain that is less than the first symbol period, wherein atotal duration of the second and third symbol periods in the time domainis less than or equal to the first symbol period of the first symbol;and communicating with the node utilizing the third symbol in the thirdresource segment in the second subframe.
 3. The method of claim 1,further comprising: determining feedback based at least in part oncommunicating with the node utilizing the second symbol; andtransmitting feedback to the node utilizing a fourth symbol on the firstcomponent carrier, the fourth symbol having the first symbol period andthe first tone spacing.
 4. The method of claim 3, wherein the feedbackcomprises at least one of channel quality information (CQI) or hybridautomatic repeat request (HARQ) feedback.
 5. The method of claim 3,wherein the feedback comprises at least one of channel qualityinformation (CQI) or hybrid automatic repeat request (HARQ) feedback. 6.The method of claim 1, wherein the first tone spacing for the one ormore subcarriers of the first symbol is 15 kHz.
 7. The method of claim1, wherein each of the first subframe and the second subframe is 1 ms.8. The method of claim 1, wherein the second subframe is a downlinksubframe.
 9. The method of claim 1, wherein the second symbol comprisesa cyclic prefix (CP) having a duration different from a CP of the firstsymbol.
 10. The method of claim 1, wherein the first component carrieris associated with a first frequency band, and the second componentcarrier is associated with a second frequency band different from thefirst frequency band.
 11. The method of claim 1, wherein the secondsymbol comprises a data signal.
 12. The method of claim 1, wherein thefirst symbol is a symbol type specified in an LTE standard, and whereinthe second symbol is a symbol type not specified in an LTE standard. 13.The method of claim 1, wherein the first symbol further comprisesinformation indicating that a third resource segment for communicating athird symbol is scheduled on the second component carrier, the thirdsymbol having a third symbol period in the time domain that is less thanthe first symbol period, wherein a total duration of the second andthird symbol periods in the time domain is less than or equal to thefirst symbol period of the first symbol, and the method furthercomprising: communicating with the UE utilizing the third symbol in thethird resource segment in the second subframe.
 14. The method of claim1, further comprising: receiving, based at least in part oncommunicating with the node utilizing the second symbol, feedbackutilizing a fourth symbol on the first component carrier, the fourthsymbol having the first symbol period and the first tone spacing. 15.The method of claim 1, wherein the first tone spacing for the one ormore subcarriers of the first symbol is 15 kHz.
 16. The method of claim1, wherein each of the first subframe and the second subframe is 1 ms.17. The method of claim 1, wherein the second subframe is a downlinksubframe.
 18. The method of claim 1, wherein the second symbol comprisesa cyclic prefix (CP) having a duration different from a CP of the firstsymbol.
 19. The method of claim 1, wherein the first component carrieris associated with a first frequency band, and the second componentcarrier is associated with a second frequency band different from thefirst frequency band.
 20. The method of claim 1, wherein the firstsymbol is a symbol type specified in an LTE standard, and wherein thesecond symbol is a symbol type not specified in an LTE standard.
 21. Themethod of claim 1, wherein the second symbol comprises a data signal.22. A method for wireless communication at a base station, comprising:determining to transmit, to a user equipment (UE), a first symbol on afirst resource segment, the first symbol having a first symbol period ina time domain; transmitting, to the UE in a first subframe of a firstcomponent carrier, the first symbol on the first resource segment, thefirst symbol comprising information indicating that a second resourcesegment for communicating a second symbol is scheduled on a secondcomponent carrier, the second symbol having a second symbol period inthe time domain that is less than the first symbol period, the firstsymbol having a first tone spacing for one or more subcarriers differentfrom a second tone spacing for one or more subcarriers of the secondsymbol; and communicating with the UE utilizing the second symbol in thesecond resource segment in a second subframe.
 23. An apparatus forwireless communication at a user equipment (UE), comprising: aprocessor, memory coupled with the processor; and instructions stored inthe memory and executable by the processor to cause the apparatus to:receive, in a first subframe of a first component carrier from a node, afirst symbol on a first resource segment, the first symbol having afirst symbol period in a time domain; determine, based at least in parton information in the first symbol, that a second resource segment forcommunicating a second symbol is scheduled on a second componentcarrier, the second symbol having a second symbol period in the timedomain that is less than the first symbol period, the first symbolhaving a first tone spacing for one or more subcarriers different from asecond tone spacing for one or more subcarriers of the second symbol;and communicate with the node utilizing the second symbol in the secondresource segment in a second subframe.
 24. The apparatus of claim 23,wherein the instructions are further executable by the processor tocause the apparatus to: determine, based at least in part on informationin the first symbol, that a third resource segment for communicating athird symbol is scheduled on the second component carrier, the thirdsymbol having a third symbol period in the time domain that is less thanthe first symbol period, wherein a total duration of the second andthird symbol periods in the time domain is less than or equal to thefirst symbol period of the first symbol; and communicate with the nodeutilizing the third symbol in the third resource segment in the secondsubframe.
 25. The apparatus of claim 23, wherein the instructions arefurther executable by the processor to cause the apparatus to: determinefeedback based at least in part on communicating with the node utilizingthe second symbol; and transmit feedback to the node utilizing a fourthsymbol on the first component carrier, the fourth symbol having thefirst symbol period and the first tone spacing.
 26. The apparatus ofclaim 25, wherein the feedback comprises at least one of channel qualityinformation (CQI) or hybrid automatic repeat request (HARQ) feedback.27. The apparatus of claim 23, wherein the first tone spacing for theone or more subcarriers of the first symbol is 15 kHz.
 28. The apparatusof claim 23, wherein each of the first subframe and the second subframeis 1 ms.
 29. The apparatus of claim 23, wherein the second symbolcomprises a cyclic prefix (CP) having a duration different from a CP ofthe first symbol.
 30. An apparatus for wireless communication at a basestation, comprising: a processor, memory coupled with the processor; andinstructions stored in the memory and executable by the processor tocause the apparatus to: determine to transmit, to a user equipment (UE),a first symbol on a first resource segment, the first symbol having afirst symbol period in a time domain; transmit, to the UE in a firstsubframe of a first component carrier, the first symbol on the firstresource segment, the first symbol comprising information indicatingthat a second resource segment for communicating a second symbol isscheduled on a second component carrier, the second symbol having asecond symbol period in the time domain that is less than the firstsymbol period, the first symbol having a first tone spacing for one ormore subcarriers different from a second tone spacing for one or moresubcarriers of the second symbol; and communicate with the UE utilizingthe second symbol in the second resource segment in a second subframe.